High illumination light emitting diodes generally use GaAs substrates or sapphire substrates, which are poor in thermal dissipation and not suitable for high power applications. Conventionally, the light emitting structure formed on the GaAs substrate or the sapphire substrate is transferred onto a silicon substrate by wafer bonding technology, and then the GaAs or sapphire substrate is removed so as to solve the thermal dissipation problem.
Horng et al. published an article entitled “AlGaInP light-emitting diodes with mirror substrates fabricated by wafer bonding” in Vol. 75, No. 20, 3054, Appl. Phys. Lett. (1999). Horng et al. disclosed an AlGaInP light emitting diode with a Au/AuBe/SiO2/Si mirror substrate by wafer bonding in which AuBe/Au is used as adhesive to bond a silicon substrate and a light emitting epitaxial layer.
U.S. Pat. No. 6,287,882 is granted to Chang et al., entitled “Light emitting diode with a metal-coated reflective permanent substrate and method for manufacturing the same”. Chang et al. disclosed a AlGaInP/metal/silicon light emitting diode by wafer bonding, which uses metal as adhesive to bond a silicon substrate and a light emitting epitaxial layer.
Therefore, there is a need to provide a light emitting diode, which is insulated from a base and suitable for high drive current operation.